The long-term objective of the Cancer Center's Chemical Library Screening Facility is to provide new chemical tools for elucidating the basic mechanisms that underlie tumor onset and progression, and to provide lead chemical compounds for initiation of the development of anti-tumor drugs. Small molecule agonists and antagonists have proven to be invaluable tools for solving problems in biology. Since high-throughput screening is not widely available at academic institutions, this facility will provide a new and unique approach toward understanding and combating cancer. The Cancer Center's Chemical Library Screening Facility was founded in mid-2002. The facility was built with funds provided by the Institute and from the fund-raising efforts of Principle Investigators. At the present time the Facility is not funded by the CCSG. The rapid success of the Facility, and the anticipated heavy demand for its services provide the rationale for the funding that is requested. The Specific Aims of the Chemical Library Screening Facility are to: 1) Establish and maintain a large chemical library, and an accompanying database, for screening against molecular targets in cancer; 2) Provide consultation to the Faculty of the Cancer Center in the design of high-throughput assays; 3) Provide high throughput screening services to the Faculty of the Cancer Center; and 4) Provide virtual screening capabilities to the Faculty of the Cancer Center.